Castro singled as a pinch-hitter in his big league debut on Wednesday night during a 5-2 win against the Red Sox.
The Braves needed Castro while shortstop Andrelton Simmons sat out with a sore hand, but with Simmons' return to the lineup on Thursday, manager Fredi Gonzalez said the team needed an outfielder off the bench rather than an infielder.
Perez has played in 26 big league games from 2012-2014, none with the Braves. This will be his first big league action of 2015. He was hitting .296 with 28 steals for the Gwinnett Braves this season.